As is well known who are familiar with and enjoy firearms, firearms create both a loud noise as well as a significant recoil when they are discharged. The noise and the recoil are generally proportional to the size of the bullets being discharged by the firearms. For example, a 22 caliber rifle produces less noise and recoil than does a high caliber hunting rifle such as a 30-06 caliber firearm. However, both large and small bore weapons generally produce an undesirably great noise and recoil when discharged. This is accurate with respect to almost all firearms including both rifles and pistols.
Previously known firearm noise suppressors, commonly referred to as "silencers", are typically threaded onto the outer end of a firearm barrel in order to reduce the noise of the firearm. These devices have been known for most of this century and all generally directed to muffling or reducing the noise of the exhausting gases created by ignition of a cartridge without necessarily retarding the passage of the bullet through the gun barrel.
Most prior art noise suppressors known to applicants are constructed to effect rapid cooling of exhausting gases and the reduction of pressure therefrom before the gases emerge from the end of the noise suppressor device. Typically, the well-known noise suppressors or "silencers" used on firearms have a large cross-sectional area providing a chamber through which a bullet passes that contains heat absorbing and/or exhaust gas-defusing materials.
Although most noise suppressors are large diameter cylindrical devices that are screwed onto the end of a firearm barrel, it is also known to provide a noise suppressor or silencer along the entire length of an enlarged-diameter rifle barrel. As with the cylindrical devices that are screwed onto the end of a conventional barrel, the full-length large diameter silencers are readily visible to anyone who observes the firearm.
Of interest with respect to this second type of noise suppressor, U.S. Pat. No. 1,487,214 to Dezendorf discloses a rifle wherein the barrel is surrounded by first sleeve and second concentric sleeves. Apertures are provided within the barrel and the first and second concentric sleeves, and the cartridge to be discharged in the firearm is provided with apertures in first and second portions along its length with a partition therebetween. In this manner, when the cartridge is discharged blast gases pass from the rear portion of the cartridge and through the first and second sleeves and back from the sleeves and into the apertures in the uppermost portion of the cartridge in order to propel the bullet projectile from the firearm barrel. Due to the tortuous path through which the blast gases pass in traveling from the explosive chamber of the cartridge and back to the second chamber immediately behind the rear of the bullet projectile, the discharge of the firearm is relatively flashless and noiseless. Also, U.S. Pat. No. 1,140,578 to Coulombe and U.S. Pat. No. 1,173,687 to Thompson disclose firearm noise suppressors or silencers that extend the entire length of an enlarged diameter rifle barrel and are constructed as an internal part of the enlarged diameter gun barrel.